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Is there anyone here running an Cobb AP tune? Because my understanding is that these tunes can hold boost numbers on point.

So if there is someone running the tune, without upgraded clamps....doesn't that mean that upgrade the clamps may not be a solution to boost creep? And instead boost creep is a product of a bad tune?

I'm not 100% sure that this is a clamp issue. Just figure I'd throw this out there.

A few people in the AP thread for 2015's have stated that they aren't hitting their boost targets. They were advised by various other members to adjust clamps or run the HWG maps. Whether or not the clamps are an issue is debatable since there aren't actual numbers/results to prove one way or the other. Could loose clamps cause a vacuum leak which would lead to lower boosts? Yes. Is it more likely that the environment doesn't require full boost to hit target torques? Probably. Yet that doesn't seem to be what this fix is proposed for as it's more focused towards boost creep.

A smoke test before/after might be worth it however it probably isn't a one size fits all problem. It might just be as simple as certain models not having their clamps tightened properly. Several people have stated that theirs were loose. Regardless I think it would be the wisest decision for everyone who owns a '15 to at the very minimum check all your clamps. If they are loose, tighten them. If you are worried that stock clamps aren't strong enough or want to prevent it from chewing up the hose, replace them. I would imagine the results are negligible and any difference from stock clamps are just a result of loose clamps in the first place.

A few people in the AP thread for 2015's have stated that they aren't hitting their boost targets. They were advised by various other members to adjust clamps or run the HWG maps. Whether or not the clamps are an issue is debatable since there aren't actual numbers/results to prove one way or the other. Could loose clamps cause a vacuum leak which would lead to lower boosts? Yes. Is it more likely that the environment doesn't require full boost to hit target torques? Probably. Yet that doesn't seem to be what this fix is proposed for as it's more focused towards boost creep.

A smoke test before/after might be worth it however it probably isn't a one size fits all problem. It might just be as simple as certain models not having their clamps tightened properly. Several people have stated that theirs were loose. Regardless I think it would be the wisest decision for everyone who owns a '15 to at the very minimum check all your clamps. If they are loose, tighten them. If you are worried that stock clamps aren't strong enough or want to prevent it from chewing up the hose, replace them. I would imagine the results are negligible and any difference from stock clamps are just a result of loose clamps in the first place.

In the case of adjusting clamps or running a HWG map, the problem is not hitting target boost. Right?

The concensus seems to be that installing better clamps will fix boost creep. If anything, loose clamps should cause a boost leak. This is why someone would recommend tightening clamps or running a HWG map.

I just don't understand how loose clamps can cause the car to boost creep. Does having loose clamps cause the wastegate to react slower? I don't think they are connected like that.

Either the wastegate is too small and cannot bypass enough gas or there is an issue with boost controller; ie the controller can't keep up or is programmed poorly.

I'm not sure what boost creep you're talking about, I haven't seen anyone present this issue, only not hitting target boost or peaking at target boost and then dropping off. I also theorized that there was no leak until max boost was hit, then the leak would express and the car would struggle and not reach target boost again. So, I ordered and replaced the clamps. Then i relogged. Then I reset the ECU, and relogged again. The logs never changed. Then I got protuned and the car is perfect. The tuner stated that it was cars like mine that make his job easy, base map and a few revisions and done.

I'm located near a Cobb shop, and many other reputable shops and vendors. Earlier today I was at a shop talking with a customer that had dyno'd at stock and at Cobb stage1 91 and 93. His result was the 91 map was 20hp below the stock map, and the 93 was 20hp over, for a net difference of 40hp. It seems to me that the generic off the shelf maps that are coming out just don't have the detail necessary to make power safely without some risk. And safety is something Cobb has always erred on the side of.

My 2015 stage1 tune feels like the jump my bugeye made from stock to stage 2. The cobb map did nothing for me but help with throttle modulation.

I found two clamps on my turbo inlet piping barely tight everything else seemed fine. I also found every clamp facing in a direction that makes it miserable to get to. I'm going to upgrade clamps in the near future.

^^Did you put the new clamps under the "rubber collar" on the IC in/out & TB? I put the clamps over them and noticed someone else put the collar on under the new clamps. That shouldn't make a difference.

I already took off the IC again to dbl check the clamps...I guess I'll dbl check the turbo inlet.

Yes I know I have to reset the ecu (does it make that much of difference besides the time it takes to learn?), but I have boost jumping between 18-20ish in 3rd. Great...

Putting the intercooler back sucks

When reasembling, a light smear of light paraffin oil or vasaline on the inside of the charge pipes allows the pipes to slide back into position very easily. This is direct from the Subaru service and repair manual so its safe to use.

So did the reset, did I do it right (pulled batt cable and pressed brakes a few times,that that always worked on my bugeye)? Only had to fix the time/date and the initial on screen agreement (limited). Trip mileage didn't reset, and driver window still had auto up/down.
I let it sit in the on position for a bit, then let it idle for a bit.

44*F 13XXft elevation. Now it max'd at 19 psi, and bounce between 17-19. Is that little bounce normal? It wasn't as bad as before I reset that was almost like 5psi with max 22.

For the hater - The only thing Im trying hard to do, is help people. I do expect some people will not like this and think it was a very simple thing to isolate and I dont deserve any credit. I mean who would have thought every clamp on a brand new engine from a reputable car maunfacturer was working loose or breaking after 3000kms? I agree, It sounds ludicrous, totally unrealistic and even more so the fact that Subaru is either unaware (still) or unwilling to rectify it. And just so you know, this is my first Subaru, and also the first turbo engine I had ever worked on so the learning curve was steep. Also worth mentioning is that I have not made a single dollar from this and I am not trying to sell anyone anything.

Anyway, for those of you who choose to do the job, I hope you enjoy the benefits. And for the people with words of encouragement, I thank you. For those that just want to spew forth abuse and criticism... well... what can you say to people like that really? I also wish you well and hope that you have a happier day tomorrow.

Well I hate that it is too cold in my garage to mess with this, though I have just bought the clamps...

Thanks for updating this thread with pictures, that I just found, it will make the job easier for sure!

As for the trolls, if it causes you any peace, they also troll other threads of NASIOC (hey, they also hate CVT's -- what a surprise!) and the best way to avoid them is using the Ignore feature.

I haven't even received my 2015 yet but after test driving several before putting my payment down, I could tell they had inconsistent boost levels and this makes sense now as to what the problem was. I told the salesman one of them drive better than another and he told me I was imagining it. Haha, and it showed 21-22psi on the max boost gauge.

I'm a little skeptical that the clamps on the pre-turbo intake tract (the third diagram) would even need to be tightened, let alone replaced. That area is under vacuum, not positive pressure, and so unless there is a damaged hose, there should be no problems. My experience on the older high-mount turbo setups is that the equivalent to the red clamp in that pic (on the high-mounts, that's the inlet-to-compressor clamp) barely had to be tightened after doing maintenance, and that in fact, tightening more than "barely" would seriously damage the inlet.

I don't feel qualified to speculate on the efficacy of the post-turbo clamps, because I don't have my WRX in my possession yet. I do find it slightly odd that the OEM clamps were able to damage a hard plastic hose, indicating to me that the clamp in the first picture (the one labeled as the condition of the TB hose after one tightening) was drastically overtightened.